The present invention relates, generally, to valve opening arrangements for valves in cylinders and, more particularly, to such arrangements including controls for adjusting opening and closing of the valves.
In diesel engines, it is often necessary to treat exhaust gases to meet emissions requirements. Some exhaust aftertreatment equipment must be at least periodically operated at high temperatures to function properly. At low engine speeds, it is typically necessary to provide an auxiliary burner in the post-turbine exhaust. Such a solution involves the use of additional fuel.
It is desirable to provide a method and equipment for adjusting exhaust gas temperature in an engine. It is also desirable to provide a method and equipment for adjusting valve opening and closing timings.
According to an aspect of the present invention, an engine with a valve opening arrangement comprises an engine comprising at least one cylinder and at least one valve for opening and closing an opening in the cylinder, the valve being spring loaded to a closed position, a movable contact surface for urging the valve to an open position, and a control arrangement at least partially connected to the contact surface and operable in a modified mode to at least one of advance opening and delay closing of the valve relative to opening and closing in a normal mode.
According to another aspect of the present invention, a method of modifying valve timing comprises, during a normal mode, moving a contact surface to apply a force to urge a spring-loaded valve to an open position, and thereafter releasing the force so the spring force moves the valve to a closed position and, during a modified mode, operating a control arrangement at least partially connected to the contact surface to at least one of advance opening and delay closing of the valve relative to opening and closing during the normal mode.
According to another aspect of the present invention, a device with a valve opening arrangement comprises at least one cylinder and at least one valve for opening and closing an opening in the cylinder, the valve being spring loaded to a closed position, a movable contact surface for urging the valve to an open position, and a control arrangement at least partially connected to the contact surface and operable in a modified mode to at least one of advance opening and delay closing of the valve relative to opening and closing in a normal mode.